Washing apparatus for coals



Sept. 4, 1928.

P. WOLF WASHING APPARATUS F R GOALS Filed Oct. 22', 1923 3 Sheets-Sheet1 Sept. 4, 1928.

P. WOLF WASHING APPARATUS FOR GOALS 3 Sheets-Sheet 2 Filed Oct. 22; 1923IIIHIHIHHHH HHHI Hll HI WW M Sept. 4, 1928. 1,682,820

' P. WOLF WASHING APPARATUS FOR GOALS Filed Oct. 22, 1923 .3Sheets-Sheet 3 Patented Sept. 4, 1928'.

PATENT OFFICE.

PHILIPPE WOLF, 0F PARIS, FRANCE.

wasnnre APPARATUS FOR coALs' Application filed October 22, 1923, SerialNo. 670,055, and in France October 24, 1922.

This invention relates to ap aratus for washing coals with pneumaticpistons of the same type as those which regulate the separation of theproducts, without any immersed mechanism, andof the same type as thosewhich utilize the thickness of the layer to be washed for the purpose ofproducing automatically the regulation of the discharge of the heavyproducts.

Washing vats with pneumatic pistons are known. In the washing vat whichforms the subject matter of this invention, the system of pistons isindependent of any mechanical drive and the frequency of the pulsationis instantly adjustable by actuating a valve. Washing vats are alsoknown in which the control of the separation of the products is effectedwithout the intervention of valves immersed in water by manuallyregulating cocks controlling the escape of air.

In the washing vat, which forms the sub ject matter of this invention,the regulation of the apparatus is automatic, whereby all supervision isdone away with, the apparatus regulating itself according to thepercentage of heavy products in the substance to be washed, and thequantity of said substance reaching the vat.

Apparatus which produce automatic regulation by means of mechanismsimmersed in the Water and the products to be evacuated and acting underconditions of defective mechanical working and under the risk of beingjammed, are also known. In the apparatus, which forms the subject matterof this invention, all mechanical parts are positioned in the air underthe best working conditions and without any possibility of amming. I

Another distinguishing feature of this washing apparatus lies in thesimultaneous evacuation of the lightest and the heaviest products at thelevel of the evacuation compartment of the heavier products.

In the accompanying drawings given by way of example: 1

Fig. 1 represents in longitudinal section a piston vat with a pnuematicpiston system for washing coals which separates the material treatedinto three products, the section being taken through the axis of thepnuematic piston system (section line A-A, Fig. 4).

Fig. 2 is a transverse section passing Fig. 5 shows in plan anarrangement consisting of several washing apparatus in series.

Fig. 6 is a sectional detail view taken on a vertical plane thru adischarge chamber of the apparatus.

Fig. 7 represents the longitudinal section through the axis of a washingvat with mechanical piston system which separates the crude coalstreated into two products.

Fig. 8 is a section along F-F, Fig. 7

The substances to be washed arrive through a chute 1 in the washing vatat one of the extremities of the washing bed which consists of aperforated sheet-iron plate 2. The substances are then shifted towardsthe other extremity, whilst becoming classified in the order of theirdensities, S, M and C indicating respectively the layers of slates,mixed substances and coals.

Towards the centre of the washing bed is provided a device which permitsthe discharge of the slates, and the lightest products,

the mixed substances and the coals, not yet separated, being separatedat the end of the apparatus.

The discharging sill for the lightest products designated by 28 islocated at the center of passages 27 which extend thru a closed chamber18. This chamber communicates thru an orifice 23 with the washing vatand an adjustable shutter 24, the inclination of which can be variedaccording to the working conditions, is provided at said orifice. Thechamber is extended downwards by means of conduits 25 thru which theslates are adapted to be discharged (see particularly Figs. 1 and At theextremity of the washing bed, opposite the point where the products tobe washed arrive, is arranged a closed chamber 19 for the evacuation ofthe mixed substances similarto the chamber 18 which also communicatesthrough an orifice 23 with the washing vat and extends downwards througha tube 26 for the evacuation of the mixed substances and forms in itsupper part a compression compartment (Fig. 6).

' ucts which device communicates through pipes 20 with the compressioncompartment of the aforesaid chambers 18 and 19 for the discharge ofslates and mixed substances.

The piston operation is pneumatic. Compressed air is conducted thru avalve 3 into a distributing chamber comprising a cylinder 5 in whichreciproeates a piston valve 4. In the position shown in Fig. 1 thepiston valve 4 is in admission position. The air passes thru orifices 5distributed around the circumference of cylinder 5 and thrucorresponding ports in the walls of the piston valve to the chamber 6 inwhich water is contained forming a part of the piston system. Whileforcing down the water in said chamber the compressed air also acts uponthe piston 4 pushing the latter upwards until it uncovers the escapeopenings 7. The escape of air thru opening 7 then continues until thepressure of the air in chamber 6 has been sufficiently reduced to causethe water to rise in chamber 6 and the piston valve 4 to fall by gravityand resume its admission position.

The amplitude of the piston range is regulated by means of the valve 3by the pressure of the compressed air and the frequency of the pistonstroke is regulated by means of a valve 8 which controls the admissionof air to and the exhaust of air from the upper part of the cylinder, 5.

It is also possible to regulate for each of its positions the speed ofthe iston valve 4, this being done by means of rod 9-carried by saidpiston valve 4 and formed with a'suitable profile, so that the sectionfor the passage of the compressed or sucked up air above the drawer maybe determined in any position of the latter.

The washing is effected as in a washing box with normal pneumaticpistons. us consider the working of the chamber 18 for the discharge ofthe slates, the working of the chamber 19 being similar. The lightestwashed ooals are evacuated at each stroke of the piston over the sill28, whilst the nonseparated mixed substances and coals are evacuatedthrough the lower passages 27 and the slates through the opening 23.

The sheet-iron, which forms a grating and limits the aperture 23 at thetop, being in front of the shutter 24 which it limits in the Let lowerpart, the slates form from the lower edge of said sheet-iron a heapwhich upon meeting the shutter 24 is incapable of statiwards thedischarge chamber 18 and its compression compartment, whilst raising andcarrying away the heap of slates which interferes with its assage up tothe chamber 18 the slates discharging through the pipes 25. It will thusbe seen that in order to regulate the evacuation of the slates throu haperture 23 it is sufiicient to regulate t e current of water flowingthrough said aperture.

With the piston stroke, the water passing through the aperture 23 risesin the compres sion chamber 18, whilst drivin back the air contained insaid chamber. I said chamber is in communication with the atmospherethere is no resistance to oppose the variation of the water level whichwill be at .a maximum as well as the current in 23 and the quantity ofevacuated slates. If on the contrary the communication between thechamber 18, and the atmosphere is cut off, the variation of the waterlevel in the'chamber 18 is progressively opposed and consequently thedischarge of the slates is diminished. If, into the chamber 18compressed air is admitted the counter pressure on the water in chamber18 opposes the rising of the level of the water under the piston strokewhereby the establishment of current in the opening 23 is prevented andthe discharge of the slates is completely stopped. a

In order to obtain automatic control of the apparatus, it is sufficientto carry out these operations automatically as function of the quantityof slates to be evacuated, that is to say, the thickness of the layer ofthe heavy products. An arrangement for the automatic regulation has beenprovided as hereunder described.

In the piston compartment 6 is 'arran ed a float 1O fixed to theextremity of a ever keyed on to a shaft rotating on supports. Said shaftcarries another lever provided with an adjusting screw 11. Said leverand the screw 11 during the working of the pistons assume an oscillatorymotion, the amplitude of which is a function of the amplitude of thepiston strokes in 6. Now as the apparatus has been regulated whenstarted, the frequency of the piston stroke is constant as well as thepressure of the compressed air and therefore the amplitude of thedisplacement of the water in the piston compartment 6 varies in aninverse ratio to the resistance opposed by the washing bed to thedisplacement of the water under the constant influence of the compressedair.

The heavier the washing bed, that is to say, the thicker the bed. ofheavy products the smaller will be the amplitude of the piston strokesin 6 and of the displacement of the screw 11. On the contrary thelighter the washing bed, that is to say, the thinner the bed of heavyproducts the greater will be the amplitude of the piston strokes in 6and of the displacement of the screw 11. The amplitude will be smallestwhen the bed of slates is so thick that the slates begin to bedischarged through the opening 27 with the mixed substances, and the bedof mixed substances so thick that the latter begin to be dischargedover'the sill 30 with the coals and it will be greatest when the bed ofslates is so thin that the mixed substances begin to be discharged belowthe gratings through the opening 23 with the slates and the bed of mixedsubstances is so thin that the coals will begin to be discharged underthe gratings through the opening 23 with the mixed substances;

The compression compartment of the chamber 18 communicates through apipe 20 with the device 17 for regulating the discharge of the slates.This arrangement consists of a cylinder in which is displaced a slide 13mounted upon a rod 12.

At every stroke of the piston, the rod is driven back by the screw 11 upto the left hand limit of the path of the latter with which it is notrigidly connected. Then the screw 11 leaves it during its movement tothe right. If any piston stroke is greater than the previous one, thescrew drives the rod 12 farther back; if it is smaller the compressedair acting in the cylinder 14 only at the time of said course end whichcorresponds to the admission of the compressed air into the pistoncompartment. 6, brings back the rod 12 into contact with the screw 11.The slide 13 is thus at any time in a position which is a function ofthe amplitude of the piston stroke.

The supply of the compressed air in the cylinder 14 is regulated bymeans of a valve 15 which retards more or less the admission of the airinto said cylinder according to the position of a screw 16 against whichit is stopped and which permits the freeescape of air from the cylinder14 when the piston system compartment 6 is open to the atmosphere. Theposition of the screw 16 is adjusted in a suitable manner, care beingtaken in the first place that the rod 12 does not come in contact withthe screw 11 before the latter has reached the limit of its displacementto the left, and secondly that the action of the compressed air is notexercised after the displacement in the opposite direction of said screw11, the result of which would be to cause the rod 12 to be displacedafter the screw 11. Such adjustment is made so that the displacement ofthe rod 12 should be in all cases very small for each supply ofcompressed air, that is to say, for each pulsation, so as to avoidirregular motions of the rod 12 and give the certainty of adjustmentwithin a'few millimeters, if the rod 12 should follow the screw 11not-hwithstanding the precautions taken.

In the event of the screw 11 passing suddenly from a great amplitude toa small one, the rod 12 would only catch it up after a few pulsationsand this has no disadvantage.

The amplitude of the pulsation of the water in G varies in inverse ratioto the weight of the washing bed as above stated.

When the quantity of slates to be evacuated is at a maximum theamplitude of the displacement of the float 10 and of the screw 11 is ata minimum and the slide 13 is in its right hand position, opening theaperture 22 for communication between the chamber 18 and the atmospherethrough the system of pipes 20 and the cylinder 17, which permits themaximum evacuation of slates.

When the quantity of slat-es to be evacuated diminishes, the amplitudeof the piston working in 6 increases, the drawer 13 shifts to the left,progressively closes the orifice 22 and then gradually opens thecommunication with the pipe system 21 which leads to the pistoncompartment 6, which at the same time diminishes the evac nation of theslates until it is completely stopped.

As above stated, the chamber of evacuation of the mixed substances 19operates in the same manner and at the same time as the chamber 18.

The arrangement which ensures the dis placement of the slide 13 asfunction of the amplitude of the piston system is shown by way ofexample. It may be replaced by any other connection: mechanical,hydraulic, magnetic, etc.

The washing apparatus which is shown in the drawings is intended for thewashing of grains,the washing of fines may be effected on felspar.

The apparatus as shown in Fig. 5 may consist .of several successivechambers for the evacuation of the heaviest products like at 18 with acorresponding arrangement for the evacuation of the lightest products.In such case sets of washing and piston compartments, successive andindependent, are arranged in series in the direction of the progress ofthe products, the capacities 18 being perpendicular to the direction ofsaid progress and the perforated bottom sheetirons of the washingcompartments being arranged atdrlecreasing levels in the direcof thecoals on to which ends the lateral channel 29 for the evacuation of thelightest products separated by successive sills 28 in combination withthe different capacities 18. Each washing and piston compartmentconsists of an apparatus for regulating the evacuation of the heavyproducts. In this way the regulating may be made as function of thequantity of slates for the compartment for the evacuation of the slatesas function of the quantity of the mixed substances for the compartmentfor the evacuation of the mixed substances instead of having aregulation function of the sum of the quantities of slates and mixedsubstances as in the apparatus illustrated in Figs. 1, 2, 3, 4.

The compressed air distributing apparatus 5 feeds a ramified system ofpipes which brings the compressed air to each of the pistoncompartments'fi 6", 6, whilst each branch of said system is providedwith a valve allowing the independent regulation of the amplitude of thepiston system in each of said compartments.

In an installation of. this type and with coals easy to wash, the widthof the washing vat would be reduced to the width of the feeding strainer1 of the coals. Then by utilizing the classification roduced in saidstrainer by the transport, the water and the coarse products, the pistonsystem would only serve to complete said classification and to producethe evacuation of the heavy products as function of the weight of thewashing bed, said evacuation bein started through lateral openingsarrange on each side of the strainer whilst a transverse aperture 23would terminate said operation and a sill similar to 28 would separatethe light est evacuated products through a strainer such as 29. I

The second' series of similar apparatus would separate the mixedsubstances from the remaining coals whilst a transverse arrangementsimilar to-the evacuation chamber 19 would terminate the operations. Thediagram of an installation of this description would only differ fromthat shown in Fig. 5 by the adj unction of lateral apertures for theevacuation of the classified dirty products.

The arrangements above described may be applied to washing vats withmechanical pistons. The piston system is effected by a piston operatedby eccentrics or any other mechanism usually employed.

The previous arrangements which do not specifically form part of thepiston apparatus are retained and the regulating apparatus for theevacuation of the s ates'is modified according to Fig. 7 whichrepresents a vat with pistons mechanically operated which separates theproducts to be washed in coals C and slates S.

The evacuation sill of the coal 30, the aperture for the evacuation ofthe slates 23' and the compression chamber 19 are retained.

Said compression chamber is connected by the pipe 20 with the cylinder35 of the regulating device for the evacuation of the slates. The pipe20 ends at an annular chamber 36 which communicates through tworectangular openings 37 with the interior of the cylinder 35 which opensit to the atmosphere. In said cylinder moves longitudinally a drawer 38rigidly attached by the rod 39 to the bell 40. The rod 39 carries akeying groove which enables it to slide longitudinally in the piece 41which forms the regulating hand wheel, but which does not enable it toturn in said piece. The hand wheel 41 can pivot 90 on the cylinder 35and be fixed in any position in said angle. The drawer also is providedwith rectangular openings 37 of the same size as those of cylinder 35.

When the drawer 38 is at the end of the high course (the case of Fig.7), the openings of the cylinder and of the drawer cor-.

respond longitudinally, which for I a particular regulation of the handwheel 41 represents the maximum of opening. The position of said handwheel makes it possible to regulate said maximum from the maximumopening which is equal to the sum of the surfaces of the two openings 37down to nil.

The cylinder 35 is furnished in its upper part with a valve 42 whichallows the air to penetrate into the cylinder under the drawer 38 whichforms a piston and does not allow it to come out again. The evacuationof said air is produced by the regulating needle 43.

The bell 40 carries a tube 44 the position of which may belongitudinally regulated in the stuffing box 45 which fixes it on to thebell.

Said bell 40 is situated in the axis of the tube 46 which passes throughthe perforated sheet-iron 2 supporting the products to be washed.

The bell has no contact with the tube; it is guided by the rod 39 andthe drawer 38.

In the case of pneumatic pistons, the pres sure in the pistoncompartment 6 (Fig. 1) is constant; in the case of mechanical pistons itis the volume of water driven back by the piston 47 which is constant.

Such constant volume in water driven back under the washing bed at eachpiston stroke lifts and raises it into the tube 46 at a height which isall the more great as the washing bed is heavier.

Towards the top of the course, the water enters the bell 40 whilstdriving back the air through the tube 44. When the water reaches thelower level of the tube 44, the upper part of the bell forms a float andcarries away the hell up to the end of the course of the Water in thetube 46. During this ascension of the bell, the drawer 38 carried awayby the rod 39 sucks up the air under it through the valve 42.

When the water goes down again it leaves the bell the lower part ofwhich fills with air :hrough the tube 44 and the whole arrangenent, thebell 40 and the drawer 38,, drops under the influence of its own weight;the ;peed of such drop is determined by the ieedle-screw 43 whichregulates the outflow if the air situated under the drawer so thatletween two pulsations, the drawer 38 should lot descend beyond a fewmillimeters.

It will thus be seen that if with one pulsaion the water rises to thesame level or iigher than with the previous one, it will aise the Wholearrangement: the bell 40 and he drawer 38, and that if it does not riseso .igh, the drawer and the bell will redescend nd again rest on thewater at the end of the igh course as a float would do.

When the bed of slates has reached its iaximum of thickness (which isthe case of ig. 7) the pulsation is at a maximum in 46, 1e drawer is atthe end of the high course, 1e compression chamber 19 is in communiitionwith the atmosphere through the orices, wide open, and the delivery ofslates :aches a maximum through the orifices 23 s has been explained inthe case of the ueumatic piston system.

If the bed of slates is reduced in thickness, [6 pulsation of the waterdiminishes parlelly in 46, the drawer descends down .e cylinder andprogressively laminates .e commuication between the compression [amber19 and the atmosphere until it is itirely cut off, which practicallystops algether the evacuation of the slates.

The tube 44 serves to regulate the position the bell relatively to thewater in the be 46, inasmuch as it permits the vertical splacement ofthe level from which such iter acts on the bell.

What I claim is:

1. In an apparatus for washing coals, the rnbination with a vat and apiston chamber mmunicating at the bottom thereof with id bat, saidchamber and vat containing iter at a desired level, of means forintroducing compressed air into said chamber and discharging sametherefrom to produce pulsation comprising an automatic valve, means fordividing the washing bed into three parts, a compression chamber andmeans controlled by the amplitude of the pulsations for placing saidcompression chamber in communication with the atmosphere or shutting itoh" and placing it in communication with piston chamber.

2. In an apparatus for washing coals, the combination with a vat and apiston chamber communicating at the bottom thereof with said vat, saidchamber and vat containing water at a desired level, of means forintroducing compressed air into said chamber and discharging sametherefrom to produce pulsations comprising an automatic valve, means fordividing the washing bed into three parts, a compression chamber, meanscontrolled by the amplitude of the pulsations for gradually placing saidcompression chamber in communication with atmosphere as the amplitudedecreases and as the layer of material increases in thickness and forgradually shutting ofl said chamber from the atmosphere as the amplitudeincreases and as the layer of material diminishes.

3. In an apparatus for washing coals, the combination with a vat and apiston chamber communicating at the bottom thereof with said vat, saidchamber and vat containing water at a desired level, of means forintroducing compressed air into said chamber and discharging sametherefrom comprising an automatic valve, means for dividing the washingbed into three parts, a compression chamber, and a valve for controllingthe" communication of the compression chamber with the atmosphere andwith the piston chamber.

4. In anapparatus for washing coals, the combination with a vat and apiston chamber communicating at'the bottom thereof with said vat, saidchamber and vat containing water at a desired level, of means forintroducing compressed air into said chamber and discharging sametherefrom comprising an automatic valve, means for dividing the washingbed into three parts, a. compression chamber, a valve controlling thecommunications of the compression chamber, and a float in the pistonchamber controlling said valve.

In testimony whereof I afiix my signature.

PHILIPPE WOLF.

